The invention relates to a device including a passage along which a liquid may be moved by application of a voltage to the liquid.
The device may be suitable for performing a chemical reaction (including biochemical reactions), for performing a chemical separation (including biochemical separations) or for performing a chemical analysis (including biochemical analyses). Alternatively, the device may be used simply to move a liquid in a controlled manner, for example to introduce a predetermined quantity of liquid into another device where a chemical reaction, separation or analysis is to take place. Other uses of the device may be envisaged.
Throughout the specification, the term xe2x80x9cliquidxe2x80x9d will be used to include solutions and also liquids that carry non-dissolved material, for example suspensions.
A device of this type is described in GB 2351245. The device of GB 2351245 is formed from first and second members having respective surfaces. A plurality of grooves are provided in the surface of the first member. The surface of the second member is connected to the surface of the first member so that each groove is closed to form a respective passage. The passages interconnect. A plurality of openings extend through the second member and form liquid reservoirs in fluid communication with the passages. Liquids placed in the reservoirs can be moved through the passages, in a controlled manner, to perform chemical reactions. In order to move the liquids, voltages are applied to the liquids, by inserting electrodes into the reservoirs.
However, the insertion of electrodes into the reservoirs obstructs the reservoir openings and this can hinder the addition or removal of liquids to or from the reservoirs. Additionally, the insertion of the electrodes into the reservoirs distorts the hydrodynamics of the reservoirs.
According to a first aspect of the invention there is provided a device including a passage along which a liquid may be moved by application of a voltage to the liquid, comprising: a passage member in which the passage is formed and having an aperture; an electrode member comprising an electrode and being separably engageable with the passage member; and wherein, when the electrode member is in said engagement with the passage member, the device has a reservoir in fluid communication with the passage for holding a liquid, the reservoir having a base, the reservoir being continuous with the aperture, and the reservoir having an opening at a surface of the passage member, electrode member cooperating with the aperture so that the electrode is in fluid communication with the passage without the electrode occupying the opening and so that the electrode is located in the reservoir adjacent the base of the reservoir.
According to another aspect of the invention there is provided a device including a passage along which a liquid may be moved by application of a voltage to the liquid, comprising: a passage member which the passage is formed and having a aperture; an electrode member comprising an electrode and being separably engageable with the passage member; and wherein, when the electrode member is in said engagement with the passage member, the device has a reservoir in fluid communication with the passage for holding the liquid, the reservoir having an opening at a surface of the passage member, the electrode member cooperating with the aperture so that the electrode is in fluid communication with the passage without the electrode member occupying the opening, and wherein the electrode member cooperates with the passage member so that the aperture sealed to prevent liquid escape there from between the electrode member and the passage member.
According to another aspect of the invention there is provided a device including a passage along which a liquid may be moved by application of a voltage to the liquid, comprising: a passage member in which said passage is formed and having at least two apertures spaced from one another; an electrode member including at least two electrodes and a member that holds the electrodes in a spacing corresponding to the spacing of the apertures; the electrode member being separably engageable with the passage member, and wherein, when the passage member is in said engagement with the electrode member, each aperture is associated with a respective one of the electrodes so that electrode is in fluid communication with the passage.